Supply device and process for supplying a patient-side coupling unit with a gas mixture

A ventilation system for artificial ventilation of a patient with a gas mixture, the gas mixture comprising a first gas component and a second gas component, wherein at least one of the two gas components is oxygen or contains oxygen, the ventilation system comprising:

• a fluid delivery unit;
• a patient-side coupling unit connected or connectable to a patient;
• and
• a supply device comprising:
• a first duct with a supply connection element configured to establish a fluid connection with a first source for the first gas component;
• a second duct;
• a mixing point;
• an inhalation duct;
• a pressure reducer with a front pressure inlet configured to establish a fluid connection with a second source for the second gas component and with a back pressure outlet, the back pressure outlet being connected to the second duct;
• a first valve configured to change a volume flow through the first duct or a pressure in the first duct or both the volume flow through the first duct and the pressure in the first duct;
• a first sensor configured to measure an indicator of pressure in the first duct or configured to measure an indicator of volume flow through the first duct;
• and
• a signal-processing control device configured to carry out a first closed-loop control to actuate the first valve during the first control as a function of measured values of the first sensor and based on a first control objective;
• wherein the first duct is configured to guide the first gas component from the supply connection element to the mixing point,
• wherein the second duct is configured to guide the second gas component from the back pressure outlet to the mixing point,
• wherein the pressure reducer is configured to provide the second gas component such that a time course of pressure at the back pressure outlet follows a time course of pressure at a reference point in the first duct,
• wherein the inhalation duct is configured to guide a gas mixture generated or emerged at the mixing point to the patient-side coupling unit,
• wherein the ventilation system is configured to carry out ventilation strokes and to guide during each ventilation stroke a respective quantity of the gas mixture through the inhalation duct to the patient-side coupling unit, and
• wherein:
• the first sensor is configured to measure an indicator of pressure, and the first control objective is the actual time course of pressure in the first duct to follow a predefined desired pressure time course;
• or
• the first sensor is configured to measure an indicator of volume flow, and the first control objective is the actual time course of volume flow through the first duct to follow a predefined desired volume flow time course.

A supply process for supplying a patient-side coupling unit with a gas mixture, the gas mixture comprising a first gas component and a second gas component, wherein the patient-side coupling unit is connected or connectable to a patient,

• the supply process being carried out with a supply device comprising a first duct with a supply connection element, a second duct, a mixing point, an inhalation duct, a pressure reducer with a front pressure inlet and with a back pressure outlet, a first valve configured to change a volume flow through the first duct or a pressure in the first duct or both the volume flow through the first duct and the pressure in the first duct, a first sensor configured to measure an indicator of pressure in the first duct or configured to measure an indicator of volume flow through the first duct, and a signal-processing control device configured to carry out a first closed-loop control to actuate the first valve during the first control as a function of measured values of the first sensor and based on a first control objective
• wherein:
• the first sensor is configured to measure an indicator of pressure and the first control objective is the actual time course of pressure in the first duct to follow a predefined desired pressure time course;
• or the first sensor configured to measure an indicator of volume flow and the first control objective being the actual time course of volume flow through the first duct to follow a predefined desired volume flow time course;
• the supply process comprises the steps of:
• providing the first gas component at the supply connection element;
• providing the second gas component at the front pressure inlet of the pressure reducer;
• the pressure reducer providing the second gas component at its back pressure outlet;
• causing a time course of a pressure at the back pressure outlet to follow a time course of pressure at a reference point in the first duct;
• guiding the first gas component from the supply connection element to the mixing point with the first duct;
• guiding the second gas component from the back pressure outlet of the pressure reducer to the mixing point with the second duct;
• the gas mixture is generated or emerged at the mixing point;
• and
• guiding the gas mixture comprising the first gas component and the second gas component from the mixing point through the inhalation duct to the patient-side coupling unit.